Plastics injection-molding machine with integrated, linear-rotary direct drive

Abstract

A plastics injection-molding machine is to be equipped with a more compact drive that undergoes less wear. For this purpose, it is envisaged to integrate the direct rotational drive into the direct linear drive. Accordingly, the electric linear motor has a pot-shaped external rotor ( 13 ), in the inner space of which the main part of a hollow-cylindrical stator ( 16 ) of the linear motor is arranged and which is firmly connected to the output shaft ( 10 ). The rotary drive has a stator ( 18 ), which is mounted on the inner wall of the hollow-cylindrical stator ( 16 ) of the linear motor, and a rotor, which is firmly coupled to the output shaft ( 10 ) within the stator ( 18 ) of the rotary electric motor. This direct drive produces a very compact type of construction and it is possible to dispense with easily wearing threaded spindles.

1. A plastics injection molding machine, comprising:
 an output drive shaft; 
 an electrical linear drive having a first electric linear motor which includes an external rotor in the form of a pot having an interior and firmly connected to the output drive shaft, and a hollow-cylindrical stator arranged in part in the interior of the first linear motor, said hollow-cylindrical stator having an interior and defining opposite axial ends; 
 an electrical rotary drive having a rotary electric motor which includes a stator with a core and winding arranged entirely in the interior of the hollow-cylindrical stator of the first linear motor and firmly connected thereto, and a rotor which is firmly coupled to the output drive shaft within the stator of the rotary electric motor; and 
 a bearing plate positioned entirely within the interior of the stator of the linear drive away from the axial ends for axial and radial support of the output drive shaft. 
 
     
     
       2. The plastics injection molding machine of  claim 1 , further comprising a plate in the form of a pot for attaching one end of the external rotor to the output drive shaft. 
     
     
       3. The plastics injection molding machine of  claim 1 , wherein the linear drive has a second electric linear motor connected in series with the first linear motor. 
     
     
       4. The plastics injection molding machine of  claim 3 , wherein the second electric linear motor has a stator, and further comprising a flange arranged between the stators of the first and second linear motors for interconnecting the stators of the first and second linear motors, said output drive shaft being supported in an area of the flange.